Seven-day consumption of sugar and other carbohydrates and challenge effects of glucose, sucrose (1.75 gm/kg), aspartame (30 mg/kg) and saccharin were compared for 32 male preschool aged children: 19 had histories of adverse behavioral response to sugar while 13 were familiar playmates with no such histories. There was no evidence of behavioral response to sugar on measures of activity, aggression, expression emotionality or anxiety. There was a slight but significant decrease in actometer rated motor activity following aspartame ingestion, the significance of which is unclear. No significant differences in dietary consumption of carbohydrate or correlations between consumption and behavior were found. The response of children with generalized anxiety disorder and of normal controls to caffeine (10 mg/kg) are being compared. To date, a total of four pairs have been examined with no evidence for greater responsivity of anxiety disordered children than controls. This is in contrast to studies with adult patients indicating caffeine hypersensitivity.